1. Field of the Invention
The present invention relates to a control apparatus for an internal combustion engine.
2. Discussion of the Background
Since fuel injection apparatuses that directly inject fuel into cylinders in internal combustion engines have relatively high drive voltages, the fuel injection apparatuses have heretofore increased their battery voltages to achieve the drive voltages. In this case, if it takes time to perform initialization after boot in electronic control units (hereinafter referred to as “ECUs”) controlling the drive voltages of the fuel injection apparatuses, there is a problem in that it takes time to achieve the drive voltages and, thus, the driving of the fuel injection apparatuses are delayed. This problem tends to be remarkable with the increasingly delayed initialization as the performance of the ECUs is improved and will be improved and the number of functions of the ECUs is increased and will be increased.
Japanese Unexamined Patent Application Publication No. 58-15737 discloses a large scale integration (LSI) device for controlling an automobile engine. This LSI device operates a circuit having an operating voltage that is lower than its battery voltage at start-up of the engine and operates a circuit having an operating voltage that is not lower than its battery voltage during normal operation.